Merge pull request #6708 from Microsoft/port-6704

Ports #6704 into release-1.8

src/compiler/binder.ts

@@ -1462,7 +1462,7 @@ namespace ts {
         function bindCallExpression(node: CallExpression) {
             // We're only inspecting call expressions to detect CommonJS modules, so we can skip
             // this check if we've already seen the module indicator
-            if (!file.commonJsModuleIndicator && isRequireCall(node)) {
+            if (!file.commonJsModuleIndicator && isRequireCall(node, /*checkArgumentIsStringLiteral*/false)) {
                 setCommonJsModuleIndicator(node);
             }
         }

src/compiler/checker.ts

@@ -10210,7 +10210,7 @@ namespace ts {
             }
 
             // In JavaScript files, calls to any identifier 'require' are treated as external module imports
-            if (isInJavaScriptFile(node) && isRequireCall(node)) {
+            if (isInJavaScriptFile(node) && isRequireCall(node, /*checkArgumentIsStringLiteral*/true)) {
                 return resolveExternalModuleTypeByLiteral(<StringLiteral>node.arguments[0]);
             }
 

src/compiler/program.ts

@@ -990,7 +990,7 @@ namespace ts {
             }
 
             function collectRequireCalls(node: Node): void {
-                if (isRequireCall(node)) {
+                if (isRequireCall(node, /*checkArgumentIsStringLiteral*/true)) {
                     (imports || (imports = [])).push(<StringLiteral>(<CallExpression>node).arguments[0]);
                 }
                 else {

src/compiler/utilities.ts

@@ -1086,12 +1086,14 @@ namespace ts {
      * exactly one argument.
      * This function does not test if the node is in a JavaScript file or not.
     */
-    export function isRequireCall(expression: Node): expression is CallExpression {
+    export function isRequireCall(expression: Node, checkArgumentIsStringLiteral: boolean): expression is CallExpression {
         // of the form 'require("name")'
-        return expression.kind === SyntaxKind.CallExpression &&
-                (<CallExpression>expression).expression.kind === SyntaxKind.Identifier &&
-                (<Identifier>(<CallExpression>expression).expression).text === "require" &&
-                (<CallExpression>expression).arguments.length === 1;
+        const isRequire = expression.kind === SyntaxKind.CallExpression &&
+            (<CallExpression>expression).expression.kind === SyntaxKind.Identifier &&
+            (<Identifier>(<CallExpression>expression).expression).text === "require" &&
+            (<CallExpression>expression).arguments.length === 1;
+
+        return isRequire && (!checkArgumentIsStringLiteral || (<CallExpression>expression).arguments[0].kind === SyntaxKind.StringLiteral);
     }
 
     /// Given a BinaryExpression, returns SpecialPropertyAssignmentKind for the various kinds of property

tests/baselines/reference/dynamicRequire.js

@@ -0,0 +1,10 @@
+//// [a.js]
+
+function foo(name) {
+    var s = require("t/" + name)
+}
+
+//// [a_out.js]
+function foo(name) {
+    var s = require("t/" + name);
+}

tests/baselines/reference/dynamicRequire.symbols

@@ -0,0 +1,10 @@
+=== tests/cases/compiler/a.js ===
+
+function foo(name) {
+>foo : Symbol(foo, Decl(a.js, 0, 0))
+>name : Symbol(name, Decl(a.js, 1, 13))
+
+    var s = require("t/" + name)
+>s : Symbol(s, Decl(a.js, 2, 7))
+>name : Symbol(name, Decl(a.js, 1, 13))
+}

tests/baselines/reference/dynamicRequire.types

@@ -0,0 +1,14 @@
+=== tests/cases/compiler/a.js ===
+
+function foo(name) {
+>foo : (name: any) => void
+>name : any
+
+    var s = require("t/" + name)
+>s : any
+>require("t/" + name) : any
+>require : any
+>"t/" + name : string
+>"t/" : string
+>name : any
+}

tests/cases/compiler/dynamicRequire.ts

@@ -0,0 +1,8 @@
+// @allowJs: true
+// @module: amd
+// @out: a_out.js
+
+// @filename: a.js
+function foo(name) {
+    var s = require("t/" + name)
+}